Pistorius, dressed in a black suit, white shirt and black tie, made his way to the dock after his lawyer Barry Roux indicated he would testify.
Pistorius looked around for his glasses as he walked to the witness box.
He was sworn in while standing and asked to stand while giving evidence.
His lawyer Brian Webber handed him a pillow.
“I would like to take this opportunity to apologise,” he said as he stood, slowly turning to his left to face Steenkamp’s mother June and relatives sitting in the front row of the public gallery.
The clacking of the laptop keyboards from the journalists in the public gallery intensified as he continued: “…to Mrs Steenkamp, Reeva’s family, to those of you who knew her…”
Judge Thokozile Masipa interjected: “I don’t like doing this to you, but I can hardly hear you.”
He continued: “I wake up every morning and you [her family] are the first people I think of, the first people I pray for…
“I was simply trying to protect Reeva.”
He said he could promise her family she felt loved when she went to bed that night.
Pistorius said he used anti-depressants and sleeping tablets after the shooting.
Pistorius’s testimony would not be televised as the court ruled only an audio broadcast would be allowed.
Pistorius is on trial for the murder of Steenkamp, who was shot through the locked toilet door of his Pretoria home on February 14 last year. He said he had mistaken her for an intruder.
He has pleaded not guilty to premeditated murder and in his plea statement denied he had argued with Steenkamp shortly before the shooting.
He also faces two charges related to contravening the Firearms Control Act.
The State closed its case on Tuesday last week after it called 21 of the 107 witnesses on its list.
– Sapa
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